The Church of San Francisco located on one side of the Plaza de Armas of Castro, Chile, is the main Catholic church of Chiloé’s capital. It has a surface area of 1,404 m2, a width of 52m and a height of 27m. The dome above the church's presbytery is 32m high and the height of its towers is 42m. The church is also known as the Iglesia Apóstol Santiago (St James Church) and erroneously as the “cathedral”, which is actually to be found in Ancud, headquarters of the diocese of the same name. The Church of San Francisco does however lead one of the 24 parishes that form this diocese.
The church was declared a Chilean National Monument in 1979 and UNESCO World Heritage Site on 30 November 2000.